Orion’s Mothering Nature

Within the great hunter’s sword is a celestial nursery

By J. Alex Knoll

A waning gibbous moon brightens much of our nights this week, reaching last-quarter Wednesday, December 6th. But as of Thursday, the near-full moon rises amid the shadows of twilight, around 5:30pm, with golden Jupiter roughly 10 degrees higher, about the span of your closed fist at arm’s-length. Look the same distance behind the moon for the star Betelgeuse, which makes the third point with the moon and Jupiter to form a nice equilateral triangle.
Betelgeuse marks the right shoulder of Orion the hunter, which climbs into full view by mid-evening. Made up of first- and second-magnitude stars, Orion is the most easily recognized constellation, visible from every inhabited part of Earth. Of those stars, all appear blue and blue-white, except for Betelgeuse, which shines a rosy red. This time of year, the giant hunter seems to be reclining above the horizon. Below Betelgeuse, marking the hunter’s belt, are three aligned stars pointing straight up, Alnitak, Anilam and Mintaka. Below the belt and opposite Betelgeuse is brilliant Rigel, which marks Orion’s foot. Rigel is the brightest star in the constellation and the 7th brightest star of all.
Tucked within the hunter’s belt is one of the treasures of the night sky, the Great Orion Nebula. Beneath Alnitak, the eastern-most of the belt stars, is a more faint trio of stars marking Orion’s sword. If you look closely at the middle of these points of lights, you’ll notice that it appears a little diffused and fuzzy. At 1,600 light years away, that’s the best you’re likely to see with the unaided eye. But with binoculars or a modest telescope, you see the star appear to glow. This is a vast cloud of interstellar gas, spanning 30 light years — more than 20,000 times the size of our own solar system. The gas is ionized and set aglow by countless nascent stars within this celestial incubator.